TW405305B - Asymmetrical encoding/decoding method and apparatus for communication networks - Google Patents

Abstract

In accord with the transmission system, encoded signals may be processed in intermediate stations and at receiving stations in an order different from the order of the original encoding process for transmission. In particular, the recovery of CDMA encoded signals does not require application of spreading/despreading codes in the original scheme or sequence of application of spreading codes. In one embodiment, code applications may be permuted without losing the original signal which has been encoded. In such applications, not all of the encoding spreading functions results in an increased spreading rate.

Description

Printed by the Central Bureau of Standards, Ministry of Economic Affairs, Shellfish Consumer Cooperative, 405305 at B7 V. Description of the Invention (彳) Field of the Invention This invention relates to the coding / decoding of communication signals', especially to the code sequence applied to the communication signals. In particular, it is about C D MA encoding and decoding of communication signals. Background of the Invention: Coded signals in communication systems often require the application of many codes. Most of these codes are applied to signals as overlapping sequences to accomplish several purposes and adjust the signals to meet a variety of signal transmission and exchange purposes. Some code examples include spreading and overspreading that are used to generate c DMA signals optimized for transmission channels. Other code processing includes error correction, signal correlation or disassociation and so on. These diversity of code applications must often be handled by a number of processing stations located between the originating and terminal stations. Normally, the signal must be decoded and re-encoded at each processing station. This represents a considerable processing effect at each station, resulting in inefficient signal transmission. ~ In other transmission processing (ie CDMA), the signal is spread or despread in several successive processing stations. These processing procedures determine whether the overall spreading rate will be changed depending on the spreading process. The spread spectrum application with a continuous spread spectrum layer is executed sequentially, and if the original signal is restored in the intermediate processing station, the despread spectrum system used for the restoration is the reverse order and the subsequent re-spread spectrum system is exactly the same as the sequence The original spread-spectrum operation at the transmitter is performed. Even if there is no need to restore the original signal, the necessary processing procedures are performed, and the transmission efficiency is greatly reduced. The size of this paper is in accordance with the Chinese National Standard (CNS) A4 specification (210X297 mm) ^-(Please read the precautions on the back before widening: 'This page) Alignment -4- 305305 A7 B7_____ 5. Description of the invention (2 ) Description of the invention: According to the present invention, the encoded signals generated from the transmitting station are processed at the intermediate station and the receiving station in a different order than the original encoding processing order. In particular, the restoration of the C DMA coded signal does not require the application of spreading / despreading codes based on the original coding sequence design or the reverse order of the spreading code application sequence. This is true for all levels of spreading in all direct-sequence methods, such as the use of codes that are despread by correlation. In addition, similar rank codes for other applications such as frequency hopping, time hopping, etc. can be rearranged. In the illustrative embodiment, transcoding can be applied without losing the original coded signal. In this type of application, not all encoding spread-spectrum functions cause an increase in spread-spectrum rate. Theoretically, the transformation applied to the code is based on the permissibility of the order of the Lebesgue integrable function based on the transformation, and at the same time, the original prediction is maintained. In the example used for special explanation, the special sequence of the unspread application of the received signal is transformed from the sequence of the original application of the spreading code in the signal transmission. Most signal processors can work on changing the sequence while preserving the original signal. Brief description of the figure: Figure 1 is a block diagram of a conventional prior art communication system using a spread spectrum C DMA signal, in which the decoding at the receiver is performed in the reverse order of the encoding before transmission; this paper size applies to China Standard (CNS) A4 Specification (210X297 mm) II IIIII Approved IIIIII Order-IIIII Line (Please read the precautions on the back before this page) Printed by the Central Government Bureau of the Ministry of Economic Affairs, Shellfish Consumer Cooperatives -5- 405305 at B7 V. Description of the invention (3) Figure 2 is a block diagram of a communication system using a spread spectrum CDMA signal, in which the decoding at the receiver is a solution of the spread spectrum function in an order different from the antisymmetric order of the encoding before transmission; Block diagram of a general communication system using direct-sequence C DMA, where the reverse decoding operation is transformed in the intermediate decoder and the receiving decoder. Figure 4 is a block diagram of a communication system using direct-sequence CDMA, where the receiving decoder Transform reverse decoding operation; Figure 5 is a block diagram of a frequency hopping CDMA communication system in which the reverse decoding operation is transformed in the receiving decoder; and Figure 6 is A block diagram of the invariance of the associated encoding and decoding functions. (Please read the precautions on the back before fing this page.) The comparison table of the main components of the printed and printed components of the Central Bureau of Standards of the Ministry of Economic Affairs 1 0 1 Input 1 0 2 Encoder function 1 0 3 Encoder function 1 0 4 Encoding Decoder function 1 0 6 channel 1 0 7 decoder 1 0 8 decoder 1 0 9 decoder 1 1 0 output 2 0 1 input 2 0 2 encoder ------------ &&; -----.-- 'IX ------ i ---------------- The size of this paper is in accordance with Chinese National Standard (CNS) A4 (210X297) %) -6- Printed by the Shellfish Consumer Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs 405305 V. Description of the invention (4) 2 0 3 Encoder 2 0 4 Encoder 2 0 5 Channel 2 0 7 Decoder 2 0 8 Decoder 2 0 9 Decoder 2 1 0 Output 3 0 1 Input 3 0 2 Encoder 3 0 3 Encoder 3 0 5 Encoder 3 0 4 Input 3 0 7 Decoder 3 1 0 Channel 3 1 2 Decoder 3 1 3 Encoder 3 1 5 Encoder 3 1 6 Channel 3 1 7 Output 3 3 1 Encoder 3 3 5 Channel 3 3 7 Decoder 3 3 9 Decoder 3 4 1 Decoder (Please read the notes on the back first (On the next page) This paper scale applies the Chinese National Standard (CNS) A4 specification (210X297 mm) 405305 A7 B7 V. Description of the invention (printed by the Beijin Consumer Cooperative of the Central Bureau of the Ministry of Economic Affairs 5 3 4 3 Output 1 1 4 0 1 Input »1 1 4 0 2 Encoding element please 1 k * 1 4 0 3 Encoding element reading 1 Back 1 4 0 5 Channel 1 Note 1 4 0 7 Decoder 1 1 1 | 4 0 8 Decoder 1 5 0 3 Encoder t. This page is installed 1 5 0 4 Encoder 'w, 1 I 5 0 5 Channel 1 1 L 5 0 6 Decoder 1 1 Order 5 0 7 Decoder 1 5 1 2 Output 1 1 I Detailed description 1 1 line In the conventional communication system, the order of the 'decoding' of receiving a CDMA signal and the initial encoding used for the 1 I transmission is completely antisymmetric. Figure 1 shows a communication system using the conventional coding configuration of 1 1 which includes an input 1 0 1 for receiving a 1 1 signal for transmission, and then provides a spreading function F 1, F i to F η 1- The three encoder functions 1 0 2, 1 0 3 and 1 〇 4 〇 coded signal system 1 is transmitted through channel 1 0 6, which channel must be wired or M > »\\ line, and reach 2 1 I There are a number of decoders 10 7, 108 and 109 and output 1 1 0 1 1 receiving positions. Each decoder provides a reverse decoding function. The decoding functions of F; 1 to F -1 2 1 1 and F -1 1 provide decoding sequences that are completely opposite to the original sequence 1 1 This paper size applies to Chinese national standards (CNS > A4 specifications (210X297 mm)- 8-Printed by 405305 of the Central Laboratories of the Ministry of Economic Affairs, Shellfish Consumer Cooperatives. 5. Description of the invention () 6. Sequence. This means that the decoding required for any processing must be answered in a thousand steps, and these steps must be passed. The reversed order of encoding is reversed. The encoding and decoding circuits are well known in the art and therefore do not need to be described in detail. The system with transformable spread spectrum spectrum decoding is shown in the communication system in Figure 2. In this example, the use of A specific type of spreading function that changes the sequence between frequency and despreading frequency. The signal initially applied to input 201 is encoded by the encoders 202, 203, and 204 with the sequential spreading functions Fi, F 2 and F n Not all spreading codes used need to increase the spreading rate. The spreading C DMA signal is transmitted to receivers with decoders 207, 208, and 209 connected in series to output 210. Decoding function F3 and Fj are not connected in the reverse order of the encoding function of the transmitting end. In any case, for each encoder F; there is a corresponding decoder F. In this configuration, the encoded signal unit is in all classes of encoding. It can be restored separately. This change in sequence allows, if necessary, the processing of a certain level of decimation / correlation code and decoding order of the encoded signal of the function. The basis is Tonelli-Hobson theory. This theory controls the Lebesgne integrable The order of the iterative integration of the function is expressed as the following result: C ((f, G), H) (t) = C (C (f, Η), G) (t) where f is the received signal, G Is the inverse spreading function, H is the inverse spreading function and G is the associated operator. The transformation system for an associated operator is shown in Figure 6, which shows the inverse spreading function Η follows G and equivalent G follows不变 The invariance of this paper. The size of this paper applies to China National Standard (CNS) Α4 specification (210X297 mm) --------- ^ ------- 1T ------ ^ (please first Read the notes on the back (, this page) -9-405305 A7 B7 Printed by the agency V. Description of invention (7) In transmitting a coded signal, it is often necessary to decode the signal to a certain intermediate class of the code in order to process it at an intermediate point or station in the entire transmission path. A transmission system for instructions requiring such processing It is shown in Fig. 3. The signal for transmission is applied to the input 3 0 1 and the spreading code is coded by the spreading codes Fi & F2 in the encoders 3 2 and 3 3. The subsequent encoder 3 0 5 receives another separate channel input and additionally encodes the output of the encoder 3 2 2 further. The auxiliary channel is applied to the input 3 0 4. The two signals are encoded in the encoder 3 05 by applying a spreading code F of 1 to the two signals. These signals are transmitted to the subsequent spread spectrum decoder 3 07 before being transmitted through channel 310 for spread spectrum code application. The intermediate station contains the application despreading code F; 1 decoder 3 1 2. Spread spectrum encoders 3 1 3 and 3 1 5 are connected in series. These encoders use spreading codes F) and Fn to retransmit signals. The encoder 3 1 3 has a separate output 317 for transmission from the output of the encoder 313. The output of the spread spectrum encoder 3 15 is applied to channel 2 3 16 for transmission to another intermediate destination station, which contains a spread spectrum encoder 3 3 1 to which the spread spectrum code F ^ is applied. The spread spectrum signal is transmitted through the channel n 335 to the despreading code FV, F respectively; 1 and F are one of a series of despreading encoders 3 3 7, 3 3 9 and 3 41. The despreading output signal is applied to the output terminal. 3 4 3 A direct sequence C DMA with a transform inverse decoder operation is shown in Figure 4. An example is shown in FIG. Signal functions A and B are applied to the input 4 0 1 r A contains X and Y and B contains Z and W. These are applied to the paper size applicable to the Chinese National Standard (CNS) A4 size (210X297 mm). Please read the notes on the back side and then the page binding line. 10- 9 405305 at B7 V. Description of the invention (

X

Y time + 0 12 time series coding table pattern repeat m 〇d12 3 4 5 6 7 8 9 10111213 + — — + + — — — + + + + + + + + + + — + ~~ — + + — W + One + One One + — + + One + One + — ---------- ^ II (Please read the notes on the back first and then one page ..) Used in frequency hopping C DMA transfer system An embodiment specifically illustrated for the use of transcoding applications is shown in FIG. The four users (X, Y, Z and W) are all depicted in the communication system. Two encoders 5 0 3 and 5 0 4 show the encoding function? 1 and? 2 in order to map users to the jump set {X, y, z, w}. The jumping set is shown as (nxyzw) at any time. The coding operator Ft is applied to make the fluorine jump pattern (nxy zw) when η is even and (nyxwz) when η is odd. F2 has (nxyzw) input. In this embodiment, n is all equal to k (mod 4). So when k = 0 or 1, F2 is (nabcd). F2 is (ncdab) when k = 2 or 3. So when k = 〇 F1F2 is (nxyzw): When k = l, F1F2 is (nyxwz): When k = 2, 'Fi F2 is (n zwxy) •, and when k = 3, F1F2 is (nw zy X). Both Fi & F2 are equal to their reciprocal and are two consecutive. This paper size applies to China National Standard (CNS) A4 (210X297 mm)

Printed by the Central Standards Bureau of the Ministry of Economic Affairs, Shellfish Consumer Cooperative, -12- 405305 A7 B7 V. Application description of the invention (Coordination. Borrow in the function to change, change in A. The transfer order 10 will lead to nabc —. When n = 0, 1, 2, 3, the transmission frequency d) can be controlled by the clock commonly used in C DMA systems by first applying? 1 and then applying? 2. Fi *, for each One clock pulse will frequency the clocks of X and Y and interactively change the clock frequencies of Z and W. The other clock pulse frequencies in function F2 * interact with those frequencies in B. These frequency interaction changes are shown in the figure The number of 5 is shown in the table. After passing through the channel 5 0 5, the decoders 5 0 6 and 5 7 decode with a change (Fi1 precedes F〗 1), and the output with all signal restoration 5 1 2 ^ The operation of the illustrative embodiment of FIG. 5 can be understood by reviewing the appended tables A to D of FIG. 5. Table A shows the encoding operations on the two groups of signals A and B whose frequencies are skipped by the encoder 5 0 3 .

Table A repeats m 〇 d 4 Please read the note on the back first # 'This page binding line Printed by the Employee Consumer Cooperative of the Central Bureau of Standards, Ministry of Economic Affairs

X Y ZZ W

Time + 0 x y Z '1 2 3 y ζ w X W ζ W X y 2 y X 4 χy ζ

y X This paper size applies to China National Standards (CNS) A4 specifications (210X297 mm) -13-405305 A7 B7 V. Description of the invention () 11 X s and Y s of subgroup A are transformed into W of subgroup B s and Z s. Every clock pulse produces an output change. These transformations are shown in Table A of Figure 5. The output of the encoder 503 is further transformed by the encoder 504 every two time units, i.e., the transformation of A and B, as shown in Table B.

Table B Time 4 X Y Z W 0 1 2 3 4 X y X y X y X y X y Z w z w z

y X

The frequency hopping transmission of B is shown in Table c in Table c l ----- ^-ΐτ ------ m (please read the precautions on the back before this page). Printing repeat m 〇d 4 time today 0 1 2 3 4 5 XX yzw X y Y y X wzy X zzw X yzwwwzy X wz This paper · size is in accordance with China National Standards (CNS) A4 specifications (210X297 mm)- 14-

Claims (1)

A8 B8 C8 D8 87t2202 g 405305 VI. Application for patent scope 1 · A method of associating the decoded spread spectrum spectrum c DMA signal 'The order of the decoded sequence is different from the reversed spectrum of the transmitted signal C DMA code sequence reverse The method includes the following steps; by successive encoding steps F 1 to? 2 Before transmission, encode with the spread spectrum signal; transmit the signal through the transmission channel; receive the signal from the transmission channel; decode the received signal by decoding the spread spectrum code with the decoding sequence of the concatenated sequence in which the application sequence is not the encoding step. One coded spreading code has a corresponding decoded and despreading code, and the spreading and despreading codes are associated correlation codes. 2. The method according to item 1 of the scope of patent application, further comprising the following steps: Part of the decoding system of the received signal: and the decoding system is allocated to several intermediate receiving stations located between the starting point and the terminal. 3. The method according to item 2 of the scope of patent application, further comprising the following steps: Repeating the encoding step and the decoding step between intermediate receiving stations. 4. The method according to item 3 of the patent application scope further includes the following steps: The intermediate and terminal stations use a spreading and despreading rate that is different from the original spreading frequency at the beginning of transmission. 5 · If the method in the scope of application for patent No. 4 further includes this paper size, use the Chinese national standard (CNS > 8 4 specifications (210X297 mm)) Please read the note I on the back first and write: This' Page Economy Ministry of Economic Affairs, Central Bureau of Commerce, Industrial and Commercial Cooperative Cooperatives, -16- B8 C8 D8 405305 々, the scope of patent application: The following steps: Add a large number of channels in the transmission path through the encoder on the intermediate receiving station. The four-item method further includes the following steps: Transmission by each channel using a majority of different decoding and coding sequences. A method of associated decoding and transformation of frequency hopping codes, wherein the transmission and reception codes have different The sequence of transformations includes the following steps: Step by step a frequency hopping encoding step F [to? 2 to skip the transmission signal frequency; transmit a series of frequency hopping signals via a transmission channel; receive a frequency hopping signal from the transmission channel; and The application sequence is not a decoding step of the transmission sequence in order to decode the received signal. --.------- »------, ιτ ------ ^ -. (Please read the precautions on the back, and then 4, as shown on this page) Printed by the Shell Consumer Cooperative of the Central Bureau of Standards of the Ministry of Economic Affairs *. This paper size is in accordance with China National Standards (CNS) Α4 (210X297 mm)- 17-